Houseplants are awesome indoor air cleaners, but some of them are more effective than others at filtering out pollutants and toxic chemicals in the air. This infographic highlights the best air-filtering plants, according to a NASA study.

NASA researchers set out to find the best ways to clean the air in space stations. Their Clean Air study found the plants below are effective at removing benzene, formaldehyde, and trichloroethylene, xylene, and ammonia from the air—chemicals that have been linked to health effects like headaches and eye irritation.

There are other benefits to having these plants around, we’ve noted before, but the graphic below from Love the Garden shows you at a glance the plants that make the best natural air filters. NASA research suggests having at least one plant per 100 square feet of home or office space. (The Snake Plant or Mother-in-Law’s Tongue is pretty hardy, by the way, although not entirely unkillable.)